| IED ID | IndEnz0002001045 |
| Enzyme Type ID | protease001045 |
| Protein Name |
Metalloprotease StcE EC 3.4.24.- Mucinase Neutral zinc metalloprotease StcE Secreted protease of C1 esterase inhibitor from EHEC |
| Gene Name | stcE tagA L7031 ECO57PM83 |
| Organism | Escherichia coli O157:H7 |
| Taxonomic Lineage | cellular organisms Bacteria Proteobacteria Gammaproteobacteria Enterobacterales Enterobacteriaceae Escherichia Escherichia coli Escherichia coli O157:H7 |
| Enzyme Sequence | MNTKMNERWRTPMKLKYLSCTILAPLAIGVFSATAADNNSAIYFNTSQPINDLQGSLAAEVKFAQSQILPAHPKEGDSQPHLTSLRKSLLLVRPVKADDKTPVQVEARDDNNKILGTLTLYPPSSLPDTIYHLDGVPEGGIDFTPHNGTKKIINTVAEVNKLSDASGSSIHSHLTNNALVEIHTANGRWVRDIYLPQGPDLEGKMVRFVSSAGYSSTVFYGDRKVTLSVGNTLLFKYVNGQWFRSGELENNRITYAQHIWSAELPAHWIVPGLNLVIKQGNLSGRLNDIKIGAPGELLLHTIDIGMLTTPRDRFDFAKDKEAHREYFQTIPVSRMIVNNYAPLHLKEVMLPTGELLTDMDPGNGGWHSGTMRQRIGKELVSHGIDNANYGLNSTAGLGENSHPYVVAQLAAHNSRGNYANGIQVHGGSGGGGIVTLDSTLGNEFSHEVGHNYGLGHYVDGFKGSVHRSAENNNSTWGWDGDKKRFIPNFYPSQTNEKSCLNNQCQEPFDGHKFGFDAMAGGSPFSAANRFTMYTPNSSAIIQRFFENKAVFDSRSSTGFSKWNADTQEMEPYEHTIDRAEQITASVNELSESKMAELMAEYAVVKVHMWNGNWTRNIYIPTASADNRGSILTINHEAGYNSYLFINGDEKVVSQGYKKSFVSDGQFWKERDVVDTREARKPEQFGVPVTTLVGYYDPEGTLSSYIYPAMYGAYGFTYSDDSQNLSDNDCQLQVDTKEGQLRFRLANHRANNTVMNKFHINVPTESQPTQATLVCNNKILDTKSLTPAPEGLTYTVNGQALPAKENEGCIVSVNSGKRYCLPVGQRSGYSLPDWIVGQEVYVDSGAKAKVLLSDWDNLSYNRIGEFVGNVNPADMKKVKAWNGQYLDFSKPRSMRVVYK |
| Enzyme Length | 898 |
| Uniprot Accession Number | O82882 |
| Absorption | |
| Active Site | ACT_SITE 447 |
| Activity Regulation | ACTIVITY REGULATION: Inhibited by divalent cation chelators such as BPS and EDTA. |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | |
| DNA Binding | |
| EC Number | 3.4.24.- |
| Enzyme Function | FUNCTION: Virulence factor that contributes to intimate adherence of enterohemorrhagic E.coli (EHEC) O157:H7 to host cells. Is able to cleave the secreted human mucin 7 (MUC7) and the glycoprotein 340 (DMBT1/GP340). Also cleaves human C1 inhibitor (SERPING1), a regulator of multiple inflammatory pathways, and binds and localizes it to bacterial and host cell surfaces, protecting them from complement-mediated lysis. Therefore, the current model proposes two roles for StcE during infection: it acts first as a mucinase, allowing passage of EHEC through the oral cavity by cleaving the salivary glycoproteins that are responsible for bacterial aggregation. Similarly, in the colon, StcE cleaves the glycoproteins that protect the intestinal epithelial surface, allowing EHEC to come into close contact with host cell membranes. Secondly, it acts as an anti-inflammatory agent by localizing SERPING1 to cell membranes. {ECO:0000269|PubMed:12123444, ECO:0000269|PubMed:15096536, ECO:0000269|PubMed:15731026, ECO:0000269|PubMed:16788173}. |
| Temperature Dependency | BIOPHYSICOCHEMICAL PROPERTIES: Temperature dependence: Optimum temperature is 37-42 degrees Celsius. Active from 4 to 55 degrees Celsius. Inactive above 60 degrees Celsius. {ECO:0000269|PubMed:16788173}; |
| PH Dependency | BIOPHYSICOCHEMICAL PROPERTIES: pH dependence: Optimum pH is 6.5-7.0. Active from pH 6.1 to 9.0. {ECO:0000269|PubMed:16788173}; |
| Pathway | |
| nucleotide Binding | |
| Features | Active site (1); Beta strand (53); Chain (1); Domain (1); Helix (17); Metal binding (3); Mutagenesis (1); Signal peptide (1); Turn (6) |
| Keywords | 3D-structure;Hydrolase;Metal-binding;Metalloprotease;Plasmid;Protease;Reference proteome;Secreted;Signal;Virulence;Zinc |
| Interact With | P05155 |
| Induction | INDUCTION: Up-regulated by the LEE (locus of enterocyte effacement)-encoded regulator ler. {ECO:0000269|PubMed:11035714, ECO:0000269|PubMed:12123444}. |
| Subcellular Location | SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:12123444}. Note=Secreted via the etp type II secretion pathway. |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | SIGNAL 1..35; /evidence=ECO:0000255 |
| Structure 3D | X-ray crystallography (2) |
| Cross Reference PDB | 3UJZ; 4DNY; |
| Mapped Pubmed ID | 22483117; |
| Motif | |
| Gene Encoded By | Plasmid pO157 |
| Mass | 99,548 |
| Kinetics | BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=0.13 uM for MUC7 {ECO:0000269|PubMed:16788173}; KM=0.27 uM for SERPING1 {ECO:0000269|PubMed:16788173}; Vmax=70.2 nM/min/ug enzyme for MUC7 cleavage {ECO:0000269|PubMed:16788173}; Vmax=66.8 nM/min/ug enzyme for SERPING1 cleavage {ECO:0000269|PubMed:16788173}; Note=Proteolytic activity is 2.5-fold more efficient with the secreted mucin MUC7 than with SERPING1.; |
| Metal Binding | METAL 446; /note=Zinc; catalytic; /evidence=ECO:0000250; METAL 450; /note=Zinc; catalytic; /evidence=ECO:0000250; METAL 456; /note=Zinc; catalytic; /evidence=ECO:0000250 |
| Rhea ID | |
| Cross Reference Brenda |